Revert of Don't set cpu architecture field on iOS in UMA logs.

components/metrics/metrics_log.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/metrics/metrics_log.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <memory>
@@ skipping 159 matching lines @@
   system_profile->set_app_version(client->GetVersionString());
   system_profile->set_channel(client->GetChannel());
   system_profile->set_application_locale(client->GetApplicationLocale());
 
 #if defined(SYZYASAN)
   system_profile->set_is_asan_build(true);
 #endif
 
   metrics::SystemProfileProto::Hardware* hardware =
       system_profile->mutable_hardware();
-#if !defined(OS_IOS)
-  // On iOS, OperatingSystemArchitecture() returns values like iPad4,4 which is
-  // not the actual CPU architecture. Don't set it until the API is fixed. See
-  // crbug.com/370104 for details.
   hardware->set_cpu_architecture(base::SysInfo::OperatingSystemArchitecture());
-#endif
   hardware->set_system_ram_mb(base::SysInfo::AmountOfPhysicalMemoryMB());
   hardware->set_hardware_class(base::SysInfo::HardwareModelName());
 #if defined(OS_WIN)
   hardware->set_dll_base(reinterpret_cast<uint64_t>(CURRENT_MODULE()));
 #endif
 
   metrics::SystemProfileProto::OS* os = system_profile->mutable_os();
   os->set_name(base::SysInfo::OperatingSystemName());
   os->set_version(base::SysInfo::OperatingSystemVersion());
 #if defined(OS_ANDROID)
@@ skipping 266 matching lines @@
   DCHECK(!closed_);
   closed_ = true;
 }
 
 void MetricsLog::GetEncodedLog(std::string* encoded_log) {
   DCHECK(closed_);
   uma_proto_.SerializeToString(encoded_log);
 }
 
 }  // namespace metrics